South Korea's military on Wednesday strongly condemned a Japanese warplane's low-altitude flight close to a South Korean warship, calling it a "provocative act."

At 2:03 p.m., a Maritime Self-Defense Force P-3 patrol plane flew close to South Korea's 4,500-ton destroyer Daejoyeong at an altitude of 60 to 70 meters just 540 meters away in international waters near Ieodo, a submerged rock south of Korea's southern island of Jeju, it said.

"This low-altitude, close-range flight toward the ship of a partner country again today is a clearly provocative act, and we cannot help but doubt Japan's intent, and (we) strongly condemn this," Suh Wook, chief director of operations at the Joint Chiefs of Staff, told a press conference.

"Should this be repeated again, we will strongly respond in line with our military's code of conduct," he added.

Japan's latest low-altitude flyby is just the third this month alone, the military said. Its aircraft also flew close to Korea's 7,600-ton destroyer Yulgok YiYi last Friday and 4,500-ton landing ship Nojeokbong on Tuesday.

A Japanese defense official rejected Seoul's claim, saying its plane was on a "normal" patrol mission, according to NHK.

A military expert in Seoul raised the possibility that Japan might have defiantly carried out such a provocative flight to cause the Korean Navy to use a weapons tracking radar to build a case against Seoul.

Hours after Wednesday's incident, the defense ministry here called in a defense attache from the Japanese Embassy in Seoul to lodge a protest.

At the time of the flyby, the destroyer "actively" communicated warnings "dozens of times," but the Japanese plane did not respond and lingered in the area, another military official here said.

"In the warning, (the military) said, 'You are approaching us. Change course. If you approach us more, we may take self-defense action,'" the official told reporters on condition of anonymity.

The Korean Navy later contacted the Japanese authorities through a hotline to lodge a protest and call for the prevention of any recurrence.

"Japan later said that it is very inappropriate to take self-defense measures against an identifiable plane of a partner country and demanded Korea retract its statement," the official said.

The Japanese authorities also insisted that its flyby was in line with international law.

"We then said that it was regrettable that the Japanese plane conducted a low-altitude flyby that could be felt as a threat to a mutually identifiable warship, and we requested Japan explain its intention," the official said.

The latest incident has further escalated tensions between Seoul and Tokyo. The two sides have been in a monthlong spat over a South Korean warship's radar operation for a humanitarian mission to rescue a North Korean warship in distress on Dec. 20.

Earlier in the day, Seoul's Defense Minister Jeong Kyeong-doo openly raised allegations of Tokyo's "political intent" in the row that appeared to be winding down following Tokyo's abrupt exit from bilateral consultations on Monday.

The minister cast Tokyo's departure from working-level dialogue with Seoul as an "exit strategy" based on its realization that it cannot overturn Seoul's argument "logically and by international law."

The tussle erupted last month when Tokyo claimed that a South Korean destroyer locked fire-control radar on its maritime patrol aircraft in the overlapping exclusive economic zones of the two countries.

Seoul rejected the charge, saying the warship was on a humanitarian mission. It later accused the Japanese plane of conducting a threateningly low-altitude flight toward its destroyer.